Short-stay visits into Ireland are now temporarily banned from 11 South American countries and South Africa.
Visa-free travel ended at midnight and will remain until March 5th as part of Government's plan to stop Covid-19 variants arriving.
The change follows remarks from Taoiseach Micheál Martin that more than half of passengers arriving into Ireland on Tuesday were returning from holidays.
He told a meeting of his parliamentary party on Wednesday evening that of 800 people who came into the country by air the previous day, 542 were Irish and 397 were on holidays.
New restrictions surrounding travel have been announced by the Taoiseach, including the requirement for passengers arriving in Ireland without evidence of a 'non-detected' Covid test to undergo mandatory quarantine for 14 days.
The number of garda checkpoints is also set to increase near the country's ports and airports, while the Government is said to be working on tightening the list of exemptions on essential workers for travel.
According to data from the Health Protection Surveillance Centre (HPSC), there have been 69 outbreaks of Covid-19 related to travel since the onset of the pandemic in Ireland.
However, officials have said this number may not be truly reflective of the number of cases coming from abroad as the State's contract tracing system does not have the capacity to trace all cases back to their origin, causing some to be categorised as community transmission instead.
According to a study by Eurosurveillance earlier this week, one flight which arrived into Ireland led to 59 people across six HSE health regions around the country.
Thirteen of the flights passengers tested positive following the flight, despite the aircraft only being at 17 per cent capacity.
